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71.
In this study, we examined the clinical significance of KRAS and MAPK1 amplification and assessed whether these amplified genes were potential therapeutic targets in type II ovarian carcinoma. Using fluorescence in situ hybridization, immunohistochemistry, and retrospectively collected clinical data, KRAS and MAPK1 amplifications were identified in 9 (13.2%) and 5 (7.4%) of 68 type II ovarian carcinoma tissue samples, respectively. Interestingly, co-amplification of KRAS and MAPK1 seemed to be absent in the type II ovarian carcinomas tested, except one case. Active phospho-ERK1/2 was identified in 26 (38.2%) out of 68 type II ovarian carcinomas and did not correlate with KRAS or MAPK1 amplification. There was no significant relationship between KRAS amplification and overall or progression-free survival in patients with type II ovarian carcinoma. However, patients with MAPK1 amplification had significantly poorer progression-free survival than patients without MAPK1 amplification. Moreover, type II ovarian carcinoma cells with concomitant KRAS amplification and mutation exhibited dramatic growth reduction following treatment with the MEK inhibitor PD0325901. These findings indicate that KRAS/MAPK1 amplification is critical for the growth of a subset of type II ovarian carcinomas. Additionally, RAS/RAF/MEK/ERK pathway-targeted therapy may benefit selected patients with type II ovarian carcinoma harboring KRAS/MAPK1 amplifications.  相似文献   
72.
For quantitative determination of 5 triterpenoid constituents, including one ganoderma alcohol (ganodermatriol) and four ganoderma acids (ganoderic acid TR, DM, A, and D), in the products of Ganoderma lucidum, an analytical system was developed using high-performance liquid chromatography. The mobile phase was a linear gradient of 2% AcOH/H2O–CH3CN, and the elution profile was monitored at 243 and 252 nm for ganoderma alcohols and acids, respectively. This system was applied to a quantitative determination of the constituents in the different stage of G. lucidum (BMC9049 strain). The analytical results indicated that the quantity and composition of these triterpenoids differed appreciably among various stages. The stage that showed the highest concentration of ganoderic acid DM and TR also showed the strongest 5α-reductase inhibitory activity. This stage (stage 5 of 6) is thus the prime stage for harvesting this strain. Further, the contents of 5α-reductase inhibitors such as ganoderic acid TR and DM in G. lucidum extracts could be a very useful indicator to assess their 5α-reductase inhibitory activity and verify their potency.  相似文献   
73.
74.
The differences in the constituents of ten ester-type gum bases used as natural food additives in Japan (urushi wax, carnauba wax, candelilla wax, rice bran wax, shellac wax, jojoba wax, bees wax, Japan wax, montan wax, and lanolin) were investigated. Several kinds of gum bases showed characteristic TLC patterns of lipids. In addition, compositions of fatty acid and alcohol moieties of esters in the gum bases were analyzed by GC/MS after methanolysis and hydrolysis, respectively. The results indicated that the varieties of fatty acids and alcohols and their compositions were characteristic for each gum base. These results will be useful for identification and discrimination of the ester-type gum bases.  相似文献   
75.
Simple chromatographic methods were applied to terpenoid resins used as gum bases. Five triterpenoid resins, mastic, dammar resin, olibanum, benzoin gum and elemi resin, and two diterpenoid resins, rosin and copal resin, were separated with normal-phase TLC. Characteristic patterns were observed for all resins. Different samples of the same resin gave identical patterns. The TLC method is a candidate for a simple identification test for terpenoids resins. Samples were then methyl-esterified and analyzed with GC/MS. All resins exhibited characteristic chromatograms for total ion current. Major constituents of all resins were detected. Unique constituents that can be used as indicators were found in every resin. Therefore, GC/MS of methyl-esterified terpenoid resins is a valuable identification method.  相似文献   
76.
Sinigrin, a glucosinolate contained in cruciferous vegetables, is converted to allyl isothiocyanate by plant myrosinase or microbial myrosinase in gut microflora. The intake of sinigrin significantly decreases the urinary nitrate + nitrite level (a nitric oxide [NO] production marker) in rats administered intraperitoneally with lipopolysaccharide (LPS). This result demonstrates that sinigrin suppresses NO production and therefore likely has an antioxidative effect in vivo.  相似文献   
77.
Atherosclerosis is a multifactorial disorder. Recent studies indicate that the plasma level of sphingomyelin, which yields ceramide, correlates with the risk of coronary heart disease. Therefore, ceramide, a well-known lipid causing apoptosis in various cell types, may contribute to atherogenesis. We examined the relationship between ceramide concentration and risk factors of atherosclerosis in normal human plasma using electrospray tandem mass spectrometry (LC-MS/MS). Major ceramides in human plasma were C24∶0 and C24∶1. The ceramide concentration showed a significant positive correlation with total cholesterol (TC) and triglycerides (TG). In addition, plasma ceramide level increased drastically at a high level of LDL cholesterol (more than 170 mg/dL). Our previous studies demonstrated that the sum of fragmented and conjugated apolipoprotein B-100 proteins (B-ox), which were products of a radical reaction of LDL as well as plasma, was a reliable index of atherosclerosis. B-ox showed a significant positive correlation with the plasma ceramide level. Based on these results, we propose that the ceramide level in human plasma is a risk factor at the early stages of atherosclerosis.  相似文献   
78.
Sandarac resin, a natural gum base, is described as "a substance composed mainly of sandaracopimaric acid obtained from the secretion of sandarac trees" in the List of Existing Food Additives in Japan. To evaluate its quality as a food additive, the main constituents in a sandarac resin product were investigated. Three constituents were isolated and identified as sandaracopimaric acid, sandaracopimarinol and 4-epidehydroabietic acid by MS and 2D-NMR. Quantification of the main constituent, sandaracopimaric acid, was performed by HPLC and its content in the product was determined to be 11.6%.  相似文献   
79.
The tribological properties of cast iron have been investigated to determine the effects of micro-texturing the surfaces. The micro-textured surfaces were prepared by shot blasting or milling using a shaper. The surfaces with groove patterns and mesh patterns had higher friction coefficients than the flat surfaces. The surfaces with dimpled patterns had lower friction coefficients than the flat surfaces. The results indicated that the dimpled pattern had a beneficial effect by decreasing the friction.  相似文献   
80.
The antibacterial activity of [60]fullerene (C60), dissolved with poly(vinylpyrrolidone) K30 (PVP), was studied. Under photo-irradiation, C60/PVP aqueous solutions showed antibacterial activity, whereas PVP solution alone or fullerene solutions in the absence of light showed no activity. These results reveal that C60 is a potentially good device as a photoinduced antibacterial agent.  相似文献   
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